But an equaliser, inevitably from Aiyegbeni Yakubu, the striker Pompey sold to Middlesbrough in the summer, resulted in a draw that was nevertheless better received on the South Coast than it was on Teesside. Boro, who travel to Switzerland to play Grasshoppers Zurich in the Uefa Cup on Thursday, were uninspired until the final stages and deserved no more than a point.
"These are the kind of games we need to be winning," said Steve McClaren, the Boro manager. "In the second half we came back into it and created enough chances to win."
Following an unexceptional first half, in which Boro had more of the ball but Portsmouth the better chances, the away side went ahead within 30 seconds of the restart. Svetoslav Todorov, newly introduced at the interval, broke down the right before cutting inside. His eventual pull-back was missed by its intended target, Zvonimir Vukic, but O'Neil was following up and side-footed home from 12 yards.
It was a lead that lasted seven minutes before Yakubu met Fabio Rochemback's corner. Bizarrely, both scorer and provider were then substituted.
Their replacements, Jimmy Floyd Hasselbaink and Mark Viduka, did inspire some late pressure from the home team but a late George Boateng drive, deflected wide, was the nearest they came.
"A draw was the target before the game so it's a good result for us, but one point after one point is not enough," said Alain Perrin, the Portsmouth manager.